Various equipment is operated by internal combustion engines, such as diesel engines. Such equipment is often designed to be operated in particularly severe environments. Examples are: military vehicles such as tanks, armored vehicles or transport construction equipment; and, agricultural, construction and mining equipment. In such environments, combustion air drawn from the environment and directed into the engine, can contain substantial particulate contaminant therein. Air cleaners are used for removal of this contaminant. Typical air cleaners utilize a filter having filter media therein, through which the intake air is directed. Particulates are deposited on or in the filter media.
In some instances, precleaners, for example cyclonic precleaners, are used before the air is directed into the barrier media. An example of such an arrangement is described in U.S. Pat. No. 5,575,826 incorporated herein by reference.
In some instances, the filter media is contained within a serviceable filter cartridge. By the term “serviceable” in this context, it is meant that the filter cartridge is of a design that is to be removed from, and be replaced in, the air cleaner, in time.
In order to extend the service lifetime for the filter cartridge, and to maintain equipment performance, in some instances it is desirable to provide for periodic cleaning of the serviceable filter cartridge, without removal of the serviceable filter cartridge from the air cleaner. This can be conducted with a pulse jet cleaning system. Examples of such systems are described in U.S. Pat. Nos. 5,575,826 and 6,676,721, incorporated herein by reference. In general with such assemblies, pulse air flow is selectively intermittently directed through selected portions of a filter cartridge, to eject collected dust from the filter cartridge. The ejected dust falls to a bottom of the air cleaner, to be scavenged therefrom by a scavenge system.
Improvements in such assemblies are generally desirable.